AGROS
According to the current Law on State Survey and Cadastre from 2015, the "AGROS" is a network of global positioning system stations for the territory of the Republic of Serbia and spatial and horizontal reference system are defined by the permanent stations network of the Republic of Serbia - AGROS.
The AGROS network is a fundamental geodetic infrastructure and the materials for implementation of geodetic reference frame in line with the European standards, which is necessary for performing geodetic works, agricultural works, civil engineering works on the infrastructural projects, development and implementation of information technologies, modernization in Serbia over a longer time period. As such, it is an important subcomponent of development and upgrading of the Republic of Serbia and the integration of the Republic of Serbia with all European trends.
This system implements the uniform reference system for all geodetic bases and cadastral tasks and facilitates overcoming the issues in positioning and for other groups of users in a highly efficient and sophisticated manner.
The necessary activities are performed towards the correct operation of the service:
Activities of the AGROS CC:
- Monitoring the work of users and constant contact with them, technical support for system users when using the service and portal of the national GNSS CORS of the Republic of Serbia.
- Checking the coordinates of the station using the SinglePointPosition and PrecisePointPosition methods.
- Monitoring of system functionality and service quality of the AGROS network in real time in the Trimble Pivot Platform working environment.
- Permanent support 365 days/24 hours, for users of the AGROS system of the Republic Geodetic Authority.
- Maintenance and control of the operation of the AGROS Trimble Pivot Platform server as the control center of the Republic of Serbia - the Republic Geodetic Authority 365 days/24 hours.
- Checking the chronological catalog of irregularities or changes in the operation of GNSS satellites due to the repositioning of orbital paths and their elimination from the correction generator of the central software units of the main server.
- Checking the results of the daily GNSS adjustments of the AGROS CORS network and verifying the positional residuals of the stations, controlling the high-precision hourly deviations of CORS receivers and satellites with the aim of their more correct treatment and more reliable results of created GNSS measurement corrections.
- Comparative control of the accuracy of baselines using RINEX data from AGROS virtual reference stations and data collected at physical CORS stations, as well as using different satellite ephemeris.
- Revision of grid files for the purposes of modeling ground displacement due to the impact of tides and atmospheric pressure (oceanography and atmospheric radiation) due to the control of the reduction of GNSS measurement errors.
- Introduction of a new IGS antenna model for calibration parameters of phase centers of GNSS antennas used in the algorithmic scheme of daily and weekly adjustments of the national network of AGROS CORS coordinates.
- Regular updating of reference national IGb14 coordinates and tectonic displacements of AGROS CORS precision point positioning (PPP) stations for compliance with the European Terrestrial Reference Frame ETRS89/ETRF2000 and temporal evolution of the national geodetic datum.
- Communication with colleagues from neighboring control centers in order to coordinate data exchange and quality control.
- Testing the received and communication parameters with all external networks that the RGA intends to or has already signed an agreement on mutual cooperation and data exchange.
- Modification, testing and execution of algorithmic procedures and modules for quality control of base station coordinates, statistical analysis of the variability of time series of coordinate differences, evaluation of the impact of tropospheric and ionospheric refraction parameters on the quality of GNSS measurements, as well as the calculation of hourly deviations of terrestrial CORS receivers and GPS/GLONASS satellites in within the framework of regular activities.
Activities of the EPN LAC - EUREF Permanent GNSS Network Local Analysis Center
- Checking the availability of navigation data on FTP and HTTPS servers of the European GNSS data centers. Analysis of processed vector errors within the Bernese software.
- Validation of redundancies of daily evaluated IGS20 coordinates of EPN stations on a weekly level by combining the modified normal equations.
- Cumulative calculation of multiannual tectonic displacements of the EPN LAC CORS stations in the Bernese environment.
- Validation of redundancy of daily evaluated IGS20 coordinates of the EPN LAC stations on a weekly level by combining reduced normal equations.
- Control of daily and weekly coordinate solutions obtained by hourly adjustments using Bernese software at 24-hour level.
- Forwarding the adjustment results (positional and height), atmospheric corrections, antenna calibration results, phase centers displacement, along with status of ephemeris - emitted and ultra-rapid for all 60 stations of the Local Analysis Center.
- Updating all LAC base stations of the Republic Geodetic Authority within the EPN center, performing continuous communication with other LAC centers and discussing obtained results and recommendations for correcting them if noted
- Activities pertaining to control of correctness and operation of stations under the procedure of inclusion in the EPN CORS stations network.
Services are defined within the active tariff package.
Within the framework of the new Trimble Pivot Platform software, it is possible to create network corrections (GPS/GLONASS) based on three network principles:
- FKP concept access point FKP_3_0
- RTCM3Net concept access point RTCM3Net
- VRS concept access point to glonass and RTX_NET and GK
